San Nicholas is, not to put too fine a point on it, a detachment of 200 or more airmen managed by the 30th space wing.
If you read between the lines, CBS asked the Navy if they launched anything and the Navy said "no" (because San Nicholas and the 30th space wing are Air Force territory). Then they asked Vandenberg if they launched anything and Vandenberg said "we haven't launched anything from Vandenberg since Friday" (because they launched something from San Nicholas).
Which is kind of exciting in its own right - Vandenberg doesn't give the first **** who shows up to watch their launches, they've got ********** bleachers set up. The only reason I wasn't at the COSMO-Skymed 4 launch on Friday is it was supposed to be the COSMO-Skymed 4 launch last Sunday and they delayed that launch four separate times.
I disagree with the ICBM-submarine theory because sub-launched missiles are tiny. That rocket looked to be at least a Delta II or possibly a Minotaur IV, both of which are too big for submarines.